In order to realize high integration of the semiconductor device, methods such as miniaturization of pattern and/or multi-layer of circuit are being developed. Among these devices, there is the technology for allowing wiring to be of multi-layer. In order to achieve a multi-layer wiring structure, a conductive layer is connected between the n-th wiring layer and the (n+1)-th wiring layer, and a thin film called interlayer insulating film is formed within the area except for the conductive layer.
A typical interlayer insulating film SiO.sub.2 film. In order to allow the operation of the device to have higher speed in recent years, it is required to lower the specific dielectric constant of the interlayer insulating film. Studies with respect to material of the interlayer insulating film are being conducted. Namely, the specific dielectric constant of SiO.sub.2 is approximately 4 and studies have focused on the development of material having a specific dielectric constant smaller than that. Realization of SiOF having specific dielectric constant of 3.5 is being developed as one of them. The inventors of this application pay attention to fluorine added carbon film having a smaller specific dielectric constant.
Meanwhile, for the interlayer insulating film, high adhesiveness (adhesion), large mechanical strength and excellent thermal stability, etc. are required in addition to small specific dielectric constant. As fluorine added carbon, trade name Teflon (polytetrafuloroethylene) is well known. However, this material has extremely bad adhesive property and has small hardness. Accordingly, even if there is employed such an approach that fluorine added carbon film is used as an interlayer insulating film, there are many unknown portions in the film property (quality). In the present state, such material is difficult to be put into practical use.